The term stopper may refer to one of the following

• Stopper, a type of a knot at the end of the rope
• Stopper, a plug or a bung.
• Stopper, a term describing an opponent of the invasion of Iraq.
• Stopper, a name sometimes used for a center fullback in soccer.
• Stopper, slang for someone who is long a futures contract and is demanding delivery of the physical commodity.
• The Milkor Stopper 37/38 mm riot gun. It fires teargas grenades and rubber bullets etc.